Data storage devices are used in a variety of applications to store and retrieve user data. The data are often stored to internal storage media, such as one or more rotatable discs accessed by an array of data transducers that are moved to different radii of the media to carry out I/O operations with tracks defined thereon.
Storage devices can be grouped into storage arrays to provide consolidated physical memory storage spaces to support redundancy, scalability and enhanced data throughput rates. Such arrays are often accessed by controllers, which in turn can communicate with host devices over a fabric such as a local area network (LAN), the Internet, etc. A virtual storage space can be formed from a number of devices to present a single virtual logical unit number (LUN) to the network.